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<DIV>This is interesting since I noticed the same problem when trying to use
Mercury as a Panadapter for another rig’s IF out. It would be really cool if
there was a checkbox say on the transverter screen that would flip I &
Q</DIV>
<DIV> </DIV>
<DIV>73</DIV>
<DIV> </DIV>
<DIV>Steve</DIV>
<DIV>G1YLB</DIV>
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<DIV style="font-color: black"><B>From:</B> <A title=warren@wpratt.com
href="mailto:warren@wpratt.com">Warren C. Pratt</A> </DIV>
<DIV><B>Sent:</B> Thursday, March 13, 2014 3:23 PM</DIV>
<DIV><B>To:</B> <A title=hpsdr@lists.openhpsdr.org
href="mailto:hpsdr@lists.openhpsdr.org">hpsdr@lists.openhpsdr.org</A> </DIV>
<DIV><B>Subject:</B> Re: [hpsdr] Hermes transmit baseband frequency reversal
?</DIV></DIV></DIV>
<DIV> </DIV></DIV>
<DIV
style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'>*****
High Performance Software Defined Radio Discussion List *****<BR><BR>
<P>
<HR>
Hi Tom,<BR><BR>I think Phil already answered the question. From the
standpoint of another software developer, I can confirm that I have seen this
too as I've developed new code. I just take the pragmatic position of
flipping I/Q and moving on. I'm not sure I've ever even mentioned it to
the firmware developers or asked about the history. The history that Phil
provided is interesting.<BR><BR>73,<BR>Warren NR0V<BR><BR>
<DIV class=moz-cite-prefix>On 3/13/2014 3:26 AM, Tom McDermott wrote:<BR></DIV>
<BLOCKQUOTE cite=mid:1394706407.65767.YahooMailNeo@web121406.mail.ne1.yahoo.com
type="cite"><PRE wrap="">***** High Performance Software Defined Radio Discussion List *****
</PRE><BR>
<FIELDSET class=mimeAttachmentHeader></FIELDSET> <BR>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: helveticaneue, helvetica neue, helvetica, arial,
lucida grande, sans-serif; COLOR: #000; BACKGROUND-COLOR: #fff">
<DIV> </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">HI,</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent"> </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">In
playing with some gnuradio sources, I am getting a baseband frequency reversal
going through Hermes.</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">This
using the definitions for I and Q in the HPSDR USB protocol document (ver
1.43).<BR></DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">That
is - a downward frequency chirping IQ baseband signal into transmit causes an
upward chirping</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">IQ
baseband signal at the receive output.</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent"> </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">It
appears that the transmit I & Q side is doing the reversal, while the
receiver seems to be normal, by testing this with an external SSB receiver,
and by using various gnuradio instrumentation.<BR></DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent"> </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">In
looking through my own code that formats I & Q into the transmit frame, I
cannot seem to find any</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">deviation
from the protocol specification (rev 1.43). Do I have a bug in my code,
or is there a known </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">issue
with Hermes that causes the frequency sign inversion on transmit?</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent"> </DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent">--
Tom, N5EG</DIV>
<DIV
style="FONT-SIZE: 16px; FONT-FAMILY: helveticaneue,helvetica neue,helvetica,arial,lucida
grande,sans-serif; COLOR: rgb(0,0,0); FONT-STYLE: normal; BACKGROUND-COLOR: transparent"> </DIV></DIV><BR>
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